It is also possible to interact with proprietary instant messaging networks such as ICQ, Yahoo!, Microsoft Messenger service or AIM through the use of "transports" (requires server-side support).
Windows Vista Service Pack 1 includes Secure Socket Tunneling Protocol, a new Microsoft proprietary VPN protocol which provides a mechanism to transport Point-to-Point Protocol (PPP) traffic (including IPv6 traffic) through an SSL channel.
Transmission Control Protocol | File Transfer Protocol | Session Initiation Protocol | User Datagram Protocol | BitTorrent (protocol) | Kyoto Protocol | Internet Protocol | Post Office Protocol | Program and System Information Protocol | proprietary | Simple Network Management Protocol | Internet Message Access Protocol | Network File System (protocol) | Hypertext Transfer Protocol | Lightweight Directory Access Protocol | Secure Real-time Transport Protocol | Real-time Transport Protocol | Simple Mail Transfer Protocol | Montreal Protocol | Communications protocol | Wireless Application Protocol | SSH File Transfer Protocol | Proprietary Governor | Remote Desktop Protocol | Point-to-Point Protocol | Internet protocol | Dynamic Host Configuration Protocol | tunneling protocol | Trivial File Transfer Protocol | Real Time Streaming Protocol |
The Secure Real-Time Media Flow Protocol (RTMFP) is a proprietary protocol suite developed by Adobe Systems for encrypted, efficient multimedia delivery through both client-server and peer-to-peer models over the Internet.
Cisco Inter-Switch Link (ISL) is a Cisco proprietary protocol that maintains VLAN information as traffic flows between switches and routers.
X.500 was considered too heavyweight to access directories, Colin Robbins implemented a proprietary protocol to solve the problem, this was then significantly re-worked by Tim Howes for DIXIE which led to the development of the Lightweight Directory Access Protocol.